Magnetic powder conveyance arrangement

ABSTRACT

Magnetic powder is conveyed along a curved guide channel from a reservoir to a container by magnets moving in close proximity with an outer side surface of the channel. The magnets are mounted on an endless driven belt. As the channel approaches the container it veers away from the belt and magnets, which causes a weakening of the holding field sufficiently to permit the powder particles to fall into the container.

waited States Patent Frederick Percival Mason Burgess Hill;

Frank Arthur Oakley Waren, Hove, both of England Apr. 13, 1970 Jan. 4, 1972 [73] Assignee Creed 8: Company Limited Brighton, Sussex, England [32] Priority Apr. 17, 1969 [3 3] Great Britain [72] inventors [21 Appl. No. [22] Filed [45] Patented [54] MAGNETIC POWDER CONVEYANCE ARRANGEMENT 4 Claims, 2 Drawing Figs.

[52] US. Cl 198/41 [51] Int. Cl 865g 17/46 [50] Field of Search 198/41;

209/218, 226; 222/DIG. l

[5 6] References Cited UNITED STATES PATENTS 3,476,232 11/1969 Merwin et al 198/41 3,165,196 1/ 1965 Alfredeen 198/41 Primary ExaminerEvon C. Blunk Assistant Examiner-Alfred N. Goodman Attorneys-C. Cornell Remsen, Jr., Walter J. Baum, Paul W.

Hemminger, Charles L. Johnson, Jr., Philip M. Bolton, Isidore Togut, Edward Goldberg and Menotti J. Lombardi, Jr.

ABSTRACT: Magnetic powder is conveyed along a curved guide channel from a reservoir to a container by magnets moving in close proximity with an outer side surface of the channel. The magnets are mounted on an endless driven belt. As the channel approaches the container it veers away from the belt and magnets, which causes a weakening of the holding field sufficiently to permit the powder particles to fall into the container.

PATENTEUJAN 4m Inventors FREDERICK PRC/yum FRANK A. O. WARfN fl/nil- 7% Agent MAGNETIC POWDER CONVEYANCE ARRANGEMENT BACKGROUND OF THE INVENTION This invention relates to magnetic printing and/or display devices, and more particularly to a magnetic powder conveying and handling arrangement associated therewith.

Magnetic printing and/or display devices are well known, and essentially comprise a magnetizable surface, such as the surface of a drum or belt, which can be selectively magnetized in accordance with the matter to be printed or displayed, the surface then being dusted" with magnetic powder which adheres to the magnetized parts so forming a powder image." The dusted surface may then be used directly for display of the powder image, or it may be used as a printing element for transferring the image to a further surface such as a paper tape or sheet.

SUMMARY OF THE INVENTION According to the present invention there is provided in a magnetic printing and/or display device a magnetic powder conveying and handling arrangement in which during use magnetic powder is transported along a channel by a magnet moving along the outer surface of a nonmagnetic wall of the channel.

More specifically, tlne invention provides a magnetic powder handling arrangement which includes a channel, means for introducing magnetic powder into the channel at one end thereof, and at least one magnet outside the channel which can be moved successively past said one end and along a nonmagnetic wall of the channel, thereby transporting successive quantities of magnetic powder along the inner surface of the wall.

BRIEF DESCRIPTION OF THE DRAWING An embodiment of the invention will now be described by way of example with reference to the accompanying drawing, in which:

FIG. 1 is a partial sectional side view of a magnetic powder handling arrangement according to the invention; and

FIG. 2 is a cross-sectional view of the arrangement of FIG. 1 taken on the line A-A.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawing, a magnetic powder handling arrangement in a magnetic printing and/or display device is comprised of a U-shaped channel 1 of nonmagnetic material. One end of channel 1 is located beneath a reservoir 2 by means of which magnetic powder 4 can be introduced into the channel. The other end of channel 1 terminates above a container 3 to which magnetic powder is transported along the channel as required, in a manner to be described. Magnetic powder in the container 3 is utilized for dusting the magnetic surface of the printing and/or display device.

For transporting the magnetic powder, two permanent magnets 5 outside channel 1 are carried on an endless belt 6. The belt is movable around two pulleys 7 and 8 by rotation of spindle l2 and is disposed adjacent the sidewall 9 of channel 1 so that when the belt travels in the direction of the arrow B each magnet 5 moves past the end of the channel at which the reservoir 2 is located and along the sidewall 9.

During each such movement the respective magnet 5 attracts a quantity 10 of the magnetic powder 4 at the end of channel 1 and transports it along the inner surface of the sidewall 9.

At the left-hand end of the channel 1, above the container 3, the magnet moves away from the sidewall 9 due to the downward curvature of the latter, and the quantity 10 of powder drops into the container 3. To prevent the powder from being attracted out of the channel directly onto the magnet the channel is closcd by a cover 11 at the left-hand end.

Thus, by moving the belt 6 each magnet causes the transportation of successive quantities of the ma etic wder 4 along the channel to replenish the supply 0 pow er in the container 3.

While the principles of the invention have been described above in connection with specific apparatus, it is to be clearly understood that this description is made only by way of example and not as a limitation to the scope of the invention as set forth in the accompanying claims.

We claim:

1. In a magnetic printing and/or display device, a magnetic powder handling arrangement comprising a channel having a nonmagnetic wall, means for introducing magnetic powder into said channel at one end thereof, and at least one movable magnet outside said channel which can be moved successively past said one end and along the nonmagnetic wall of said channel, thereby transporting successive quantities of magnetic powder along the inner surface of the wall, said nonmagnetic wall being a sidewall of the channel.

2. A magnetic powder handling arrangement according to claim 1 wherein said at least one movable magnet is carried by an endless belt.

3. A magnetic powder handling arrangement according to claim 1 wherein said channel at its other end is arranged to curve away from the path of movement of said at least one magnet, causing thereby a reduced magnetic holding field in the area of said other end.

4. A magnetic powder handling arrangement according to claim 3 wherein said other end of said channel is curved to open above a powder receptacle permitting thereby the magnetic powder conveyed along said channel to drop into the receptacle.

i i i 

1. In a magnetic printing and/or display device, a magnetic powder handling arrangement comprising a channel having a nonmagnetic wall, means for introducing magnetic powder into said channel at one end thereof, and at least one movable magnet outside said channel which can be moved successively past said one end and along the nonmagnetic wall of said channel, thereby transporting successive quantities of magnetic powder along the inner surface of the wall, said nonmagnetic wall being a sidewall of the channel.
 2. A magnetic powder handling arrangement according to claim 1 wherein said at least one movable magnet is carried by an endless belt.
 3. A magnetic powder handling arrangement according to claim 1 wherein said channel at its other end is arranged to curve away from the path of movement of said at least one magnet, causing thereby a reduced magnetic holding field in the area of said other end.
 4. A magnetic powder handling arrangement according to claim 3 wherein said other end of said channel is curved to open above a powder receptacle permitting thereby the magnetic powder conveyed along said channel to drop into the receptacle. 